Receptacle cleaning apparatus

ABSTRACT

Apparatus for cleaning a receptacle such as a bulk milk tank having an entrance and an exit comprising means for flowing a prerinse liquid such as water through the receptacle without substantial recirculation for a selected time to flush out foreign material, means for thereafter circulating a quantity of rinse liquid such as an additional amount of water through a circuit including the receptacle by way of its entrance and exit for a selected time for a further rinsing action, means for removing this latter liquid at the end of its selected time, means for thereupon circulating a quantity of detergent liquid such as aqueous detergent solution through the circuit and means for removing this detergent liquid. In the preferred structure these various cleaning means are operated automatically at the proper time for the preselected time. Also, in a further preferred structure, there is provided means for circulating a preselected quantity of cleaning rinse solution such as a weak aqueous acid solution through the receptacle circuit for a selected time subsequent to the removal of the detergent liquid to produce a final removal of foreign material from the interior of the receptacle.

United States Patent Donald F. Swanson; Wynn G. Winkler. both of St. Paul, Minn.

[72] lnventors [54] RECEPTACLE CLEANING APPARATUS Primary ExaminerRobert L. Bleutge Att0rney-Hofgren, Wegner, Allen, Stellman and McCord ABSTRACT: Apparatus for cleaning a receptacle such as a bulk milk tank having an entrance and an exit comprising means for flowing a prerinse liquid such as water through the receptacle without substantial recirculation for a selected time to flush out foreign material, means for thereafter circulating a quantity of rinse liquid such as an additional amount of water through a circuit including the receptacle by way of its en- 9 chums 3 Drawing Figs. trance and exit for a selected time for a further rinsing action, [52] US. Cl 134/58, means f removing this latter liquid at the end f its selected 134/100 134/168 time, means for thereupon circulating a quantity of detergent [51] Int. Cl..... B08b 3/02, liquid Such as aqueous detergent Solution through the circuit Bosh 9/08 and means for removing this detergent liquid. In the preferred 01' Search .t 95, tructure the e various cleaning means are opgrated automati- 169 C cally at the proper time for the preselected time. Also, in a 56 R f Ced further preferred structure, there is provided means for circu- 1 e erences I lating a preselected quantity of cleaning rinse solution such as UNITED STATES PATENTS a weak aqueousacid solution through the receptacle circuit 2,558,628 6/1951 Redin 134/95 for a selected time subsequent to the removal of the detergent 3,236,248 2/1966 Ray .1 134/168 X liquid to produce a final removal of foreign material from the 3,278,961 10/1966 Syensson 134/169 X interior of the receptacle.

HOT WATER 1, cow WATER 50 3| 4 32 I I 4s r i 38 39 4o 4: 42 l 69 F 29 46 1 44 e ,9- B .0 5 i I i l 1 I 49 I I I I l I L] g U I 46o 4: ta

mus: DETERGENT 5 I8 PATENTEI] JUN29|97I 3 589378 HOT WATER 35 36 V37 FIGI COLD WATER 4 50 3| 32 I 48 33 I :U

as 39 40 41 42 i 69 I 28 L 29 L] lL/ 46o--1" 3 W440 RINSE DETERGENT l5 I8 L E f 5| 52 53 54 5s 5s 57 71'' l 70 4| :9 58L 48 30 TIMER so 38 2| 6o vw nss 7 SOLENOID FUNCTMS 79 VALVES so oRAm 54 Q4 8 72!? 24 28 4o HOTGDET. 52

ommss 33 63 :9 COLD s5 56 73 74 PUMP as 78 TIMER 5? INVENTORS.

DONALD E SWANSON ATTORNEYS.

RIECIEPIIACLE CLEANING APPARATUS One of the features of this invention is to provide an apparatus for cleaning a receptacle such as a bulk milk tank with the apparatus of the structure set out above.

Other features and advantages of the invention will be apparent from the following description of one embodiment thereof as illustrated in the accompanying drawings. Of the drawings:

FIG. 1 is a view partially semischematic and partially in sectional elevation of a tank cleaning apparatus embodying the invention.

FIG. 2 is a simplified wiring diagram showing the arrangement in the electrical circuit of the electrically operated valves in this embodiment.

FIG. 3 is a simplified view of the timer program through which the various parts of the apparatus are operated.

As shown in the accompanying drawings the invention is illustrated as embodied in a washing apparatus for a bulk milk tank having an interior 11 functioning as a receptacle to retain the milk.

The tank 10 has a top 12 with a pair of removable covers 13 arranged side-by-side to cover similar access openings. Mounted on the top wall 12 is an electric motor 14 for driving a downwardly extending agitating paddle 15. The top wall 12 intermediate the removable covers 13 is provided with an opening 16 through which is insertable a conduit 17 carrying on its lower end a spray nozzle 18. The conduit 17 and nozzle 18 are only inserted in the opening 16 when it is desired to clean the interior of the tank or receptacle 10. This same opening may also be used for inserting a dip stick or the like for measuring the amount of liquid such as milk within the receptacle.

In addition to the entrance to the tank 10 embodied in the opening 16 and spray nozzle 18 there is also provided a bottom exit 19 for draining liquid from the tank. During the cleaning of the tank the exit 19 is connected by a removable hose 20 to an electrically powered pump 21 having an intake 22 and an outlet 23. This outlet 23 is connected to a liquid exhaust line 24 that exhausts to a place of disposal such as a sewer as indicated by the arrow 25.

The pump outlet 23 is also provided with a liquid circulation flow conduit 26 having one end connected to the exhaust line 24 by a T-connection 27 and the other end connected to the spray nozzle conduit 17 as by another T-connection 28. This circulation flow conduit 26 has in it a one-way valve 29 that permits flow in the conduit 26 only toward the nozzle 18. An electrically operated solenoid valve 30 controls flow through the exhaust line 24 and thus also functions to direct flow through the circulation conduit 26 when the solenoid valve 30 is closed.

In order to control the flowing of cleaning liquids there is provided a control panel assembly 31 to which is supplied a cold water conduit 32 having two branch lines 33 and 34 and a hot water conduit 35 having two branch lines 36 and 37. The cold water branch line 33 has in it a flow controlling solenoid valve 38 and the cold water branch line 34 has a similar solenoid valve 39. Hot water lines 36 and 37 have similar solenoid valves 40 and 411, respectively.

Cold water line 34 and hot water line 37 empty into a manifold pipe 42. Hot water line 36 is connected to a detergent containing reservoir or canister 43 from which an exhaust conduit 44 leads to the manifold 42.

The cold water line 33 empties into a reservoir or canister 45 for a suitable weak acid rinse liquid such as a chlorine containing solution, or a solution of the iodophor type. The interior of this canister 45 exhausts through a conduit 46 into the manifold 42.

Check valve means comprising ball check valves 44a and 46a, disposed at the lower ends of conduits 44 and 46, respectively, prevent water from lines 44 or 46 entering the canisters 43 and 45 in the reverse direction and thus diluting the acid rinse or wetting the detergent before called for in the cycle sequence. If a relatively small amount of water should enter the canister 43 in the reverse direction, the resulting wetting of the detergent could cause it to cake. However, with full flow in the desired direction, via line 36, there is no caking problem.

Also forming a part of the control panel assembly 31 is a timer 47 including the usual motor (not shown), an operating switch 48 and a programmer 63 (FIG. 3) divided into units of time and carrying spaced electrically conducting areas for operating the various electrically controlled portions of the apparatus including the solenoid valves and pump.

The assembly 31 also has thereon a general control switch 49 and a transformer 50. This transformer provides low voltage for remote energization of the drain solenoid valve 30.

The various switches of the timer 47' are illustrated in FIG. 2 by the switches 51 to 57. The various portions of the apparatus controlled by these switches are also illustrated in this Figure. The timer control of the switches is schematically illustrated by the broken line 58 connection from the timer 47 to the series of switches. As illustrated in FIG. 2 the manual switch 49 controls the power supply to the electrical portions of the apparatus from the power source 59 and 60. From the one side 59 of the power source there is an electric line 61 that contains the manual switch 49. From the other side 60 of the power source there is the electric line 62.

As illustrated, the transformer 50 which is controlled by the switch 51 supplies low voltage power to the solenoid drain valve 30. The timer switch 52 is in series with the detergent supply solenoid valve 40. The hot water supply solenoid 41 is in series with the timer switch 53 to be controlled thereby while the rinse solution solenoid valve 38 and the cold water supply valve 39 are each in series with the timer control switches 54 and 55, respectively. Finally, the pump 21 is in series with the timer control valve switch 56 and the timer motor itself is in series with the control switch 57.

The relationship of the various timer switches to the sole' noid valves and the pump and the timer is illustrated in FIG. 3. As also shown in FIG. 3, the programmer 63 controls the various portions of the apparatus for a full 28 minute cycle. The illustrated cycle of operation is as follows.

When the timer control switch 48 is initiated the timer switch 51 is closed as indicated by the program strip 64 for 2 minutes to open the drain solenoid 30, the hot water supply solenoid valve 41 is energized to open position by the timer switch 53 for 4 minutes as indicated by the strip 65, the cold water supply solenoid valve 39 is energized to open for another 4 minutes as shown by the strip 66, the pump is energized by the timer switch 56 for 2 minutes as shown by the program strip 67 and the timer switch 57 is closed to remain closed for the entire cycle as indicated by the strip 68.

This means that for the first 2 minutes the drain 30 is open and the pump 21 through its switch 56 is energized so that hot water is directed through the solenoid valve 41 and cold water through its solenoid valve 39 and both are directed into the manifold 42 where they are mixed and flow from the manifold through a conduit 69 into the spray head 18 where the water flushes the interior surface of the tank 10. Because the pump 21 is operating and the drain valve 30 is open this water is not recirculated but flows directly to the drain as indicated by the arrow 25 to flush out any loose or water soluble foreign material from the interior 11 of the tank. At the end of this 2 minute period the drain valve 30 is deenergized to closed position and the pump is deenergized with the result that for the next 2 minutes while the hot water and cold water continue to flow the tank 10 is filled with medium temperature water.

At the end of this 4 minutes the pump 56 is again energized for 4 minutes as indicated by the strip 70 in FIG. 3 so that this contained water is drawn from the tank exit 19 through the pump 21 up through the circulation flow conduit 26 because the drain valve 30 is closed, through the check valve 29, through the spray noule 18 into the interior of the tank and then back again through this circuit. This circulation of warm water is continued for the first 2 minutes of the 4 minutes after which the timer switch 51 is closed to energize the drain valve 30 to open position as indicated by the strip 7 1. During this 2 minutes of the 4 minutes while the pump is operating the water is pumped out to the drain.

At the end of these first 8 minutes the pump is deenergized for the next 2 minutes while the hot water solenoid valves 40 and 41 are energized to open position as indicated by the strips 72 and 73 in FIG. 3. During this 2 minute interval hot water is directed through the line 36 into the detergent canister 43 and up the conduit 44 into the mixing manifold 42. At the same time hot water flows directly into the manifold through the other line 37. From the manifold 42 the resulting detergent solution flows through the conduit 69 and the spray nozzle 18 into the interior of the tank 10 and collects there because the pump and drain valve 30 are deenergized.

At the end of these 2 minutes while detergent solution is supplied to the tank 10 the hot water valves 40 and 41 are deenergized to closed position and the pump 21 is energized for 10 minutes as indicated by the strip 74. During this 10 minute period the hot detergent solution is circulated through the above-described circuit that includes the interior 11 of the tank, the pump 21, the circulation flow conduit 26 and back to the spray nozzle 18. This circulation of detergent is actually terminated for the last 2 minutes of the i minute period when the pump is in operation because during this final 2 minutes the drain solenoid valve is energized to open position as indicated by the strip 75 in FIG. 3. During this 2 minutes the hot detergent is pumped through the open drain valve 30 to disposal and at the end of this 2 minutes the drain valve 30 is deenergized and the pump 21 is deenergized.

Then, during the next 2 minute interval as indicated by the strips 76 and 77 the hot water valve 41 and the cold water valve 38 are energized to open positions. During this 2 minute interval cold water flows through the line 33 into the rinse canister 45 and then from there the resulting rinse solution flows through the conduit 46 into the manifold 42. The opening of the hot water valve 41 also supplies hot water to the manifold 42 for mixing with the cold rinse solution. The resulting rinse solution flows during this 2 minute period through the conduit 69 and spray nozzle 18 to the interior 1! of the tank 10. These 2 minute fill periods provide a preselected quantity ofliquid to the interior of the tank.

At the end of this 2 minutes the pump 21 is energized by the closing of the timer switch for 6 minutes as indicated by the strip 78 in FIG. 3. During the first 4 minutes of this 6 minute period during which the drain valve is closed the hot rinse solution is circulated through the above-described circuit that includes the pump 21, conduit 26, nozzle 18 and the interior of the tank. For the last 2 minutes of this 6 minute period that the pump is operating the drain valve 30 is energized to open position by the timer switch 51 as indicated by the strip 79 in FIG. 3 so that the rinse solution is then pumped from the tank to terminate the cycle. At the end of the above-described cycle of operation which as is illustrated in the embodiment shown is for 28 minutes the timer 47 opens its control switch 57 to stop all operations. Then the manual control switch 49 can be opened until the next automatic cleaning operation is to be performed.

The relationship of the motor 14 to the electrical circuitry has not been shown or described because if forms no part of the present invention.

As can be seen from the above description the various combinations and subcombinations of the cleaning operations are easily automatically controlled by very simple structures and simple circuitry. Furthermore, the equipment can be easily installed and arranged for automatic operation. One of the important factors in the apparatus of this invention is the providing of the initial prerinse as described where liquid such as water is flushed directly through the apparatus to remove water soluble and loose foreign material. Customarily these are recirculated through the system but the apparatus of this invention flushes them directly to the drain. Then, this is followed by the supplying ofa quantity of water to the interior of the receptacle or tank 10 with this quantity then being circulated through a system including the interior of the tank for further preliminary cleaning. it is not until this has been done that the detergent wash is used.

Another very important advantage of the apparatus of this invention is that draining of each liquid after use is done by positive pumpout action and not by relatively slow gravity. This serves to speed up the entire cycle.

Having described our invention as related to the embodiment shown in the accompanying drawings, it is our intention that the invention be not limited by any of the details of description, unless otherwise specified, but rather be construed broadly within its spirit and scope as set out in the accompanying claims.

We claim:

1. Apparatus for cleaning a bulk milk tank having an exit opening, comprising: a cold water supply line; a hot water supply line; a water soluble detergent reservoir; a spray nozzle insertable into said tank; an energizable pump having an intake connectable to said tank exit opening and an outlet; conduit means for directing cold water from said cold water supply line directly to said nozzle; conduit means for directing hot water from said hot water supply line directly to said nozzle; conduit means for directing hot water from said hot water supply line through said detergent reservoir to said nozzle; a liquid circulation flow conduit from said pump outlet to said nozzle; a liquid exhaust line from said pump outlet; an energizable flow control valve in each of said lines; and timer means for energizing said pump and energizing said valves in preselected sequence to control flow through the corresponding said lines in said sequence.

2. Apparatus for cleaning a bulk milk tank having an exit opening, comprising: a cold water supply line; a hot water supply line; a water soluble detergent reservoir; a spray nozzle insertable into said tank; an energizable pump having an intake connectable to said tank exit opening and an outlet; conduit means for directing cold water from said cold water supply line to said nozzle; conduit means for directing hot water from said hot water supply line to said nozzle; conduit means for directing hot water from said hot water supply line through said detergent reservoir to said nozzle; a liquid circulation flow conduit from said pump outlet to said nozzle; a liquid exhaust line from said pump outlet; an energizable flow control valve in each of said lines; timer means for energizing said pump and energizing said valves in preselected sequence to control flow through the corresponding said lines in said sequence, said spray nozzle being supplied from said'lines through a supply conduit and said liquid circulation flow conduit emptying into said supply conduit; and a check valve means in said flow conduit for permitting flow therethrough toward said nozzle only.

3. Apparatus for cleaning a bulk milk tank having an exit opening, comprising: a cold water supply line; a hot water supply line; a water soluble detergent reservoir; a spray nozzle insertable into said tank; an energizable pump having an intake connectable to said tank exit opening and an outlet; conduit means for directing cold water from said cold water supply line to said nozzle; conduit means for directing hot water from said hot water supply line to said nozzle; conduit means for directing hot water from said hot water supply line through said detergent reservoir to said nozzle; a liquid circulation flow conduit from said pump outlet to said nozzle; a liquid exhaust line from said pump outlet; an energizable flow control valve in each of said lines; timer means for energizing said pump and energizing said valves in preselected sequence to control flow through the corresponding said lines in said sequence; a manifold conduit connected to said cold water supply line to receive water therefrom, connected to said hot water supply line to receive water therefrom, and connected to said detergent reservoir to receive detergent therefrom; a hot water line to said detergent reservoir; and a flow control valve in said detergent hot water line.

4. The apparatus of claim 3 wherein there are provided a rinse composition reservoir, a conduit from said rinse reservoir to said manifold, a cold water line to said rinse reservoir, and a flow control valve in said rinse reservoir water line.

5. The apparatus of claim 4 wherein each of said valves in said hot water line to said detergent reservoir and said rinse reservoir line is energizable, and said timer means is for energizing these valves also in preselected sequence.

6. The apparatus of claim 5 wherein said spray nozzle is supplied from said lines through a supply conduit, said liquid circulation flow conduit empties into said supply conduit, and there are provided means for preventing flow in the reverse direction through each of said reservoirs and a check valve means in said flow conduit for permitting flow therethrough toward said nozzle only.

7. The apparatus of claim 2 wherein said timer means preselected sequence energizes said hot water, cold water and exhaust line valves to open positions and energizes said pump to provide a water prerinse through said tank without recirculation, then deenergizes said exhaust line valve to closed position and deenergizes said pump to supply a quantity of water to said tank, then energizes said pump while maintaining said exhaust line valve deenergized to circulate said water in a circuit including said tank, pump, circulation flow conduit and nozzle, and then energizes said exhaust line valve while maintaining said pump energized to remove said water from the tank.

8. The apparatus of claim 7 wherein there are provided a manifold conduit connected to said cold water supply line to receive water therefrom, connected to said hot water supply line to receive water therefrom, and connected to said detergent reservoir to receive detergent therefrom, a hot water line to said detergent reservoir and a flow control valve in said detergent hot water line, each of said valves in said hot water line to said detergent reservoir and said rinse reservoir waterline is energizable, said timer means preselected sequence after said removal of the water from the tank then energizes the valve in said detergent hot water line and the valve in said hot water supply line to open positions while maintaining said pump deenergized to introduce a quantity of hot aqueous detergent solution to said tank, then energizes the pump while maintaining the exhaust line valve deenergized to circulate said detergent solution in said circuit, and then energizes said exhaust line valve while maintaining said pump energized to remove said detergent solution from the tank.

9. The apparatus of claim 8 wherein there are provided a rinse composition reservoir, a conduit from said rinse reservoir to said manifold, a cold water line to said rinse reservoir, and a flow control valve in said rinse reservoir water line, said timer means preselected sequence after said removal of said detergent solution from said tank then energizes said valve in said water line to said rinse reservoir and said valve in said hot water supply line to open position wlhile deenergizing said exhaust line valve to closed position and deenergizing said pump to introduce a quantity of rinse solution to said tank, then energizes the pump to circulate said rinse solution in said circuit, and then energizes said exhaust line valve while maintaining said pump energized to remove said rinse solution from the tank. 

1. Apparatus for cleaning a bulk milk tank having an exit opening, comprising: a cold water supply line; a hot water supply line; a water soluble detergent reservoir; a spray nozzle insertable into said tank; an energizable pump having an intake connectable to said tank exit opening and an outlet; conduit means for directing cold water from said cold water supply line directly to said nozzle; conduit means for directing hot water from said hot water supply line directly to said nozzle; conduit means for directing hot water from said hot water supply line through said detergent reservoir to said nozzle; a liquid circulation fLow conduit from said pump outlet to said nozzle; a liquid exhaust line from said pump outlet; an energizable flow control valve in each of said lines; and timer means for energizing said pump and energizing said valves in preselected sequence to control flow through the corresponding said lines in said sequence.
 2. Apparatus for cleaning a bulk milk tank having an exit opening, comprising: a cold water supply line; a hot water supply line; a water soluble detergent reservoir; a spray nozzle insertable into said tank; an energizable pump having an intake connectable to said tank exit opening and an outlet; conduit means for directing cold water from said cold water supply line to said nozzle; conduit means for directing hot water from said hot water supply line to said nozzle; conduit means for directing hot water from said hot water supply line through said detergent reservoir to said nozzle; a liquid circulation flow conduit from said pump outlet to said nozzle; a liquid exhaust line from said pump outlet; an energizable flow control valve in each of said lines; timer means for energizing said pump and energizing said valves in preselected sequence to control flow through the corresponding said lines in said sequence, said spray nozzle being supplied from said lines through a supply conduit and said liquid circulation flow conduit emptying into said supply conduit; and a check valve means in said flow conduit for permitting flow therethrough toward said nozzle only.
 3. Apparatus for cleaning a bulk milk tank having an exit opening, comprising: a cold water supply line; a hot water supply line; a water soluble detergent reservoir; a spray nozzle insertable into said tank; an energizable pump having an intake connectable to said tank exit opening and an outlet; conduit means for directing cold water from said cold water supply line to said nozzle; conduit means for directing hot water from said hot water supply line to said nozzle; conduit means for directing hot water from said hot water supply line through said detergent reservoir to said nozzle; a liquid circulation flow conduit from said pump outlet to said nozzle; a liquid exhaust line from said pump outlet; an energizable flow control valve in each of said lines; timer means for energizing said pump and energizing said valves in preselected sequence to control flow through the corresponding said lines in said sequence; a manifold conduit connected to said cold water supply line to receive water therefrom, connected to said hot water supply line to receive water therefrom, and connected to said detergent reservoir to receive detergent therefrom; a hot water line to said detergent reservoir; and a flow control valve in said detergent hot water line.
 4. The apparatus of claim 3 wherein there are provided a rinse composition reservoir, a conduit from said rinse reservoir to said manifold, a cold water line to said rinse reservoir, and a flow control valve in said rinse reservoir water line.
 5. The apparatus of claim 4 wherein each of said valves in said hot water line to said detergent reservoir and said rinse reservoir line is energizable, and said timer means is for energizing these valves also in preselected sequence.
 6. The apparatus of claim 5 wherein said spray nozzle is supplied from said lines through a supply conduit, said liquid circulation flow conduit empties into said supply conduit, and there are provided means for preventing flow in the reverse direction through each of said reservoirs and a check valve means in said flow conduit for permitting flow therethrough toward said nozzle only.
 7. The apparatus of claim 2 wherein said timer means preselected sequence energizes said hot water, cold water and exhaust line valves to open positions and energizes said pump to provide a water prerinse through said tank without recirculation, then deenergizes said exhaust line valve to closed position and deenergizes said pump to supply a quantity of water to said tank, then energizes said pump whiLe maintaining said exhaust line valve deenergized to circulate said water in a circuit including said tank, pump, circulation flow conduit and nozzle, and then energizes said exhaust line valve while maintaining said pump energized to remove said water from the tank.
 8. The apparatus of claim 7 wherein there are provided a manifold conduit connected to said cold water supply line to receive water therefrom, connected to said hot water supply line to receive water therefrom, and connected to said detergent reservoir to receive detergent therefrom, a hot water line to said detergent reservoir and a flow control valve in said detergent hot water line, each of said valves in said hot water line to said detergent reservoir and said rinse reservoir water line is energizable, said timer means preselected sequence after said removal of the water from the tank then energizes the valve in said detergent hot water line and the valve in said hot water supply line to open positions while maintaining said pump deenergized to introduce a quantity of hot aqueous detergent solution to said tank, then energizes the pump while maintaining the exhaust line valve deenergized to circulate said detergent solution in said circuit, and then energizes said exhaust line valve while maintaining said pump energized to remove said detergent solution from the tank.
 9. The apparatus of claim 8 wherein there are provided a rinse composition reservoir, a conduit from said rinse reservoir to said manifold, a cold water line to said rinse reservoir, and a flow control valve in said rinse reservoir water line, said timer means preselected sequence after said removal of said detergent solution from said tank then energizes said valve in said water line to said rinse reservoir and said valve in said hot water supply line to open position while deenergizing said exhaust line valve to closed position and deenergizing said pump to introduce a quantity of rinse solution to said tank, then energizes the pump to circulate said rinse solution in said circuit, and then energizes said exhaust line valve while maintaining said pump energized to remove said rinse solution from the tank. 